A high-temperature resistant, room-temperature curing anti-corrosion coating and its preparation method

Abstract

This invention relates to a high-temperature resistant, room-temperature curing anti-corrosion coating and its preparation method. The high-temperature resistant, room-temperature curing anti-corrosion coating includes component A and component B. Component A includes epoxy resin, small molecule hydroxyl compounds, additives, and inorganic fillers. Component B includes a curing agent. The epoxy resin includes phenolic epoxy resin, which includes various phenolic epoxy resins with different viscosity gradients. The coating of this invention, by using phenolic epoxy resins with different viscosity gradients, can improve the adhesion between the coating and oil pipeline materials, and also improves the resistance to different temperatures and humidity levels. It has strong adhesion to oil pipelines, is easy to apply, and possesses a variety of excellent properties such as high solids content, impermeability, corrosion resistance, high temperature resistance, and thermal stress resistance. It can be applied in harsh environments such as alternating high and low temperatures, alternating dry and wet conditions, alternating strong acids and alkalis, and high abrasion, and is suitable for long-term corrosion protection of oil pipelines.

Description

Technical Field

[0001] This invention relates to the field of oilfield development technology, specifically to a high-temperature resistant, room-temperature curing anti-corrosion coating and its preparation method. Background Technology

[0002] As development progresses through the later stages in some oilfield blocks, water cut and temperature gradually increase, coupled with rising levels of CO2, H2S, and Cl in some oil and gas wells. - The high content of corrosive media in oil pipelines leads to harsh service environments and frequent corrosion and perforation problems. Inner coatings are an effective way to solve corrosion problems within oil pipelines, but the harsh service environment places high demands on the performance of these coatings. On the other hand, with increasingly stringent national safety and environmental protection requirements, the development trend of high-temperature resistant, room-temperature curing anti-corrosion coatings is towards low VOC emissions, green environmental protection, and energy conservation and emission reduction.

[0003] Currently, high-temperature resistant internal coatings all require baking and curing at around 220 degrees Celsius, resulting in high energy consumption. Conventional room-temperature curing coatings are suitable for oil and gas field surface pipeline systems and equipment, but cannot meet the requirements of the high-temperature, high-pressure, and highly corrosive media service environment downhole and the requirements of SY / T 6717 "Technical Conditions for Inner Coatings of Tubing and Casing". While patent 202010258962.2 discloses an anti-corrosion coating, in practical applications it contains a relatively high amount of small molecules, which easily leads to particle or small molecule migration, thus affecting its resistance to different temperatures and humidity levels. Therefore, there is an urgent need to develop high-temperature resistant room-temperature curing anti-corrosion coatings and corresponding preparation methods. Summary of the Invention

[0004] In order to solve one or more technical problems existing in the prior art, the present invention provides a high-temperature resistant, room-temperature curing anti-corrosion coating and its preparation method.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: a high-temperature resistant, room-temperature curing anti-corrosion coating, comprising component A and component B, wherein component A comprises epoxy resin, small molecule hydroxyl compound, additives and inorganic filler, and component B comprises curing agent;

[0006] The epoxy resin includes phenolic epoxy resin, which includes a variety of phenolic epoxy resins with different viscosity gradients.

[0007] The beneficial effects of this invention are as follows: The coating of this invention uses epoxy resin as the base material. In actual use, different epoxy resins have different properties, and the characteristics of the resulting coatings will vary greatly. To achieve better durability of the coating, the epoxy resin includes phenolic epoxy resin. Moreover, by using phenolic epoxy resins with different viscosity gradients, the adhesion between the coating and the oil pipeline can be improved, and it is also beneficial to improve the tolerance to different temperatures and humidity. It has strong adhesion to the oil pipeline and is easy to apply. It has a variety of excellent properties such as high solid content, impermeability, corrosion resistance, high temperature resistance, and thermal stress resistance. It can be applied in harsh environments such as high and low temperature alternation, dry and wet alternation, strong acid and strong alkali alternation, and high wear, and is suitable for long-term corrosion protection of oil pipelines.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Furthermore, to further improve the adhesion of the obtained coating to the surface of oil pipes and its resistance to different temperatures and humidity, the phenolic epoxy resin includes phenolic epoxy resin with a viscosity of 1000-2000 mPa·s at 25°C and phenolic epoxy resin with a viscosity of 7000-20000 mPa·s at 25°C.

[0010] The epoxy equivalent of the phenolic epoxy resin with a viscosity of 1000-2000 mPa·s at 25°C is 176-181 g / eq; the preferred phenolic epoxy resin with a viscosity of 1000-2000 mPa·s at 25°C is Dow 438-X8.

[0011] The epoxy equivalent of phenolic epoxy resin with a viscosity of 7000-20000 mPa·s at 25℃ is 14-16 kg / eq; the domestic linear phenolic epoxy resin EPN1183 (product model) can be selected for the phenolic epoxy resin with a viscosity of 7000-20000 mPa·s at 25℃.

[0012] The beneficial effects of adopting the above-mentioned further solutions are: using phenolic epoxy resin with specific viscosity and epoxy equivalent can improve the adhesion between the coating and the oil pipe, and is conducive to improving the tolerance to different temperatures and humidity.

[0013] Furthermore, the epoxy resin also includes organosilicon epoxy resin, and the weight ratio of the phenolic epoxy resin to the organosilicon epoxy resin is 1:(0.25~0.45).

[0014] The silicone epoxy resin includes a variety of silicone epoxy resins with different viscosity gradients.

[0015] The beneficial effect of adopting the above-mentioned further solution is that the combination of phenolic epoxy resin and silicone epoxy resin improves the temperature resistance of the coating. In actual operation, it was also found that the weight ratio of phenolic epoxy resin to silicone epoxy resin needs to be further controlled at 1:(0.25~0.45), because when the silicone epoxy resin content is high, the coating becomes brittle, and its resistance to damp heat and adhesion are poor.

[0016] Optionally, the weight ratio of phenolic epoxy resin to silicone epoxy resin is 1:0.25, 1:0.3, 1:0.35, 1:0.4, or 1:0.45.

[0017] Furthermore, the silicone epoxy resin comprises a Forte 4 cup silicone epoxy resin with a viscosity of 20–80 s at 25°C and a silicone-modified epoxy resin with a viscosity of 15,000–20,000 mPa·s. The weight ratio of the silicone epoxy resin with a viscosity of 20–80 s at 25°C to the silicone-modified epoxy resin with a viscosity of 15,000–20,000 mPa·s is 1:(1.6–2.7).

[0018] Optionally, the weight ratio of organosilicon epoxy resin with a viscosity of 20-80 s at 25°C to organosilicon modified epoxy resin with a viscosity of 15000-20000 mPa·s is 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2.0, 1:2.1, 1:2.2, 1:2.3, 1:2.4, 1:2.5, 1:2.6, or 1:2.7.

[0019] Among them, the silicone epoxy resin with a viscosity of 20-80s at 25℃ and a cup-4 coating can be Wuxi Xiano New Materials RE-611 (product model) silicone epoxy resin.

[0020] For silicone-modified epoxy resins with a viscosity of 15,000–20,000 mPa·s, Dow Corning SF-8413 silicone-modified epoxy resin can be selected.

[0021] The beneficial effects of adopting the above-mentioned further solutions are: using organosilicon epoxy resin with a specific viscosity gradient can further improve the adhesion between the coating and the oil pipe, and also help to further improve the tolerance to different temperatures and humidity.

[0022] In the experiment, phenolic epoxy resin and silicone epoxy resin with different viscosity gradients were selected to achieve better spreading of the coating during practical use and improve the adhesion between the coating and the oil pipe. At the same time, the use of specific silicone epoxy resins is also beneficial to the compatibility between different epoxy resins, thereby improving the intermolecular forces of the coating, thus improving the toughness and hardness of the resulting coating, and also improving the tolerance to different temperatures and humidity. However, when the content of the small viscosity gradient components of phenolic epoxy resin and silicone epoxy resin in the system is low or high, it can lead to a decrease in the mechanical properties of the coating and its tolerance to different temperatures and humidity.

[0023] Furthermore, the small molecule hydroxy compound is trimethylolpropane triglycidyl ether.

[0024] The beneficial effects of adopting the above-mentioned further solutions are: by using specific small molecule hydroxyl compounds, it is possible to achieve good spreadability of the coating while solving the problems of moisture resistance and high temperature resistance of the coating.

[0025] This invention utilizes small-molecule polyhydroxy compounds to regulate the viscosity of the resulting coating. However, in practical use, it has been found that the coating's resistance to moisture and high temperatures decreases when small-molecule polyhydroxy compounds are added to the system. This is related to the type and content of the small-molecule polyhydroxy compounds. To avoid this problem, this invention uses trimethylolpropane triglycidyl ether as the small-molecule polyhydroxy compound, which also reduces the content of small-molecule hydroxy compounds in the system (trimethylolpropane triglycidyl ether contains epoxy groups in its structure, which directly reduces the hydroxyl content). In addition, trimethylolpropane triglycidyl ether contains epoxy groups, which helps to improve its interaction with the epoxy resin of a specific viscosity in this system and reduce the exudation of small-molecule hydroxy compounds in the system, thereby achieving a better spreading effect of the coating with a lower content of small-molecule hydroxy compounds.

[0026] Furthermore, the curing agent includes polyetheramine with a total amine value of 0.5 to 1.1 Meq / g and m-phenylenediamine, and further, the mass ratio of polyetheramine to m-phenylenediamine is 1:(0.4 to 0.6); by controlling the mass ratio of polyetheramine to m-phenylenediamine, the resulting coating achieves better heat resistance.

[0027] The primary amine content of the polyetheramine is not less than 95%, and the viscosity at 25°C is 200–700 mPa·s.

[0028] Furthermore, the polyetheramine includes D2000 (25℃, 200-300 mPa·s; total amine value 0.98-1.03 Meq / g; primary amine content ≥ 97%) and T3000 (25℃, 600-700 mPa·s; total amine value 0.90-0.98 Meq / g; primary amine content ≥ 97%) from the Hongbaoli polyetheramine series, with a weight ratio of D2000 to T3000 of 1:(0.5-0.7).

[0029] Optionally, the weight ratio of D2000 to T3000 is 1:0.5, 1:0.55, 1:0.6, 1:0.65, or 1:0.7.

[0030] The beneficial effects of adopting the above-mentioned further solutions are as follows: The curing agent described in this invention is used for curing epoxy resin-based coatings. The choice of curing agent will also affect the coating's tolerance to different temperatures and humidity levels. In the epoxy resin coating system of this invention, specific amine values, primary amine ratios, and polyetheramines with different gradients are used as curing agents. This is beneficial for maintaining sufficient contact between the curing agent and the epoxy resin base material, achieving a better curing effect under specific amine values ​​and primary amine ratios. At the same time, it can also ensure that the resulting coating maintains a certain hardness and wear resistance, and avoids molecular migration during use, thereby improving tolerance to different temperatures and humidity levels.

[0031] Furthermore, component B also includes a curing accelerator; furthermore, the curing accelerator is salicylic acid, wherein it has been found that when the content of the salicylic acid is 1 to 3% of the mass content of the curing agent, the toughness of the resulting coating is better, and too high or too low salicylic acid content will affect the toughness of the resulting coating after it is applied to the substrate surface.

[0032] Furthermore, the inorganic filler has a BET specific surface area of ​​150–300 m². 2 / g of fumed silica, wherein the sample density (silica density) of the inorganic filler is 30-50g / L.

[0033] The beneficial effects of adopting the above-mentioned further solutions are: adding inorganic fillers to the system of the present invention further improves the flow properties of the coating; however, problems such as coating stratification or poor flowability may still occur during the addition process. To avoid these problems, the inorganic filler of the present invention has a BET specific surface area of ​​150-300 m². 2 The preferred sample density is 30–50 g / L fumed silica, such as Wacker fumed silica. H2O (BET is 170-230m) 2 / g, sample density 40g / L); using fumed silica with specific specific surface area and density, such as Wacker fumed silica. H2O can be well dispersed in the system, while avoiding problems such as coating layering or poor flowability, and also avoiding the coating viscosity being too low, which would affect the surface hardness, wear resistance or tolerance to different temperatures and humidity.

[0034] Optionally, the inorganic filler has a BET specific surface area of ​​150 m². 2 / g, 160m 2 / g、170m 2 / g、180m 2 / g、190m 2 / g、200m 2 / g、210m 2 / g、220m 2 / g、230m 2 / g、240m 2 / g、250m 2 / g、260m 2 / g、270m 2 / g、280m 2 / g、290m 2 / g, or 300m 2 / g of fumed silica.

[0035] Optionally, the sample density of the inorganic filler is 30 g / L, 31 g / L, 32 g / L, 33 g / L, 34 g / L, 35 g / L, 36 g / L, 37 g / L, 38 g / L, 39 g / L, 40 g / L, 41 g / L, 42 g / L, 43 g / L, 44 g / L, 45 g / L, 46 g / L, 47 g / L, 48 g / L, 49 g / L, or 50 g / L.

[0036] In practical use, additives such as dispersants, defoamers, leveling agents, wetting agents, and pigments can be added according to actual needs. In some embodiments, the additive is a defoamer, which can be selected from lower alcohols, ester defoamers, polyether defoamers, mineral oil defoamers, and organosilicon defoamers.

[0037] Furthermore, by weight, component A comprises 50-70 parts epoxy resin, 5-10 parts small molecule hydroxyl compound, 2-5 parts additives and 2-5 parts inorganic filler, and component B comprises 20-30 parts curing agent;

[0038] The epoxy resin includes phenolic epoxy resin, which comprises two phenolic epoxy resins with different viscosity gradients. The weight ratio of the phenolic epoxy resin with a smaller viscosity gradient to the phenolic epoxy resin with a larger viscosity gradient is 1:(2.5-3.8).

[0039] Optionally, the weight ratio of phenolic epoxy resin with a smaller viscosity gradient to phenolic epoxy resin with a larger viscosity gradient is 1:2.5, 1:2.6, 1:2.7, 1:2.8, 1:2.9, 1:3.0, 1:3.1, 1:2.5–3.2, 1:2.5–3.3, 1:2.5–3.4, 1:2.5–3.5, 1:2.5–3.6, 1:2.5–3.7, or 1:2.5–3.8.

[0040] The beneficial effects of adopting the above-mentioned further scheme are: by limiting the weight ratio of two phenolic epoxy resins with different viscosity gradients, the adhesion of the obtained coating to the surface of oil pipes and its tolerance to different temperatures and humidity are further improved.

[0041] A method for preparing a high-temperature resistant, room-temperature curing anti-corrosion coating includes the following steps:

[0042] S1, after the epoxy resin and small molecule hydroxy compound are mixed evenly, the additives and inorganic fillers are added in sequence and stirred on a high-speed dispersant. After stirring, the mixture is allowed to stand to obtain component A material.

[0043] S2, when used, mix the A component material obtained from S1 with the curing agent to obtain a high-temperature resistant, room-temperature curing anti-corrosion coating.

[0044] The beneficial effects of this invention are: the preparation method of this invention is simple to operate and convenient to carry out. Detailed Implementation

[0045] The principles and features of the present invention are described below. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0046] Example 1

[0047] Example 1 provides a high-temperature resistant, room-temperature curing anti-corrosion coating. By weight, the coating comprises: Component A: 65 parts epoxy resin, 7 parts small molecule hydroxyl compound, 3.5 parts additives, and 3.5 parts inorganic filler; Component B: 25 parts curing agent and 0.5 parts curing accelerator.

[0048] Epoxy resins include phenolic epoxy resins and silicone epoxy resins, with a weight ratio of phenolic epoxy resin to silicone epoxy resin of 1:0.35.

[0049] The phenolic epoxy resin includes phenolic epoxy resin with a viscosity of 1000-2000 at 25℃ and phenolic epoxy resin with a viscosity of 7000-2000 at 25℃; and the weight ratio of the phenolic epoxy resin with a viscosity of 1000-2000 at 25℃ (Dow, DEN438-X8, 1000-2000 mPa·s at 25℃, epoxy equivalent of 176-181 g / eq) and the phenolic epoxy resin with a viscosity of 7000-20000 at 25℃ (domestic linear phenolic epoxy resin EPN1183, 7000-11000 mPa·s at 25℃, epoxy value of 6.3-6.9 Eq / kg) is 1:3.2.

[0050] The silicone epoxy resins include RE-611 (purchased from Wuxi Xiano New Materials, Forecast cup 4, viscosity at 25℃ is 20-80s) and Dow Corning SF-8413 (viscosity at 25℃ is 15000-20000mPa·s), with a weight ratio of 1:2.2.

[0051] The small molecule polyhydroxy compound is trimethylolpropane triglycidyl ether;

[0052] Curing agents include polyetheramine and m-phenylenediamine;

[0053] The mass ratio of polyetheramine to m-phenylenediamine is 1:0.5;

[0054] Polyetheramines include the D2000 and T3000 of the Hongbaoli polyetheramine series, with a weight ratio of 1:0.7 between D2000 and T3000.

[0055] The curing accelerator is salicylic acid;

[0056] The inorganic filler is fumed silica, specifically Wacker fumed silica. H2O (BET is 170-230m) 2 / g, sample density is 40g / L);

[0057] The additive is an antifoaming agent, specifically VK.DF553;

[0058] The coating preparation method described in this embodiment includes the following steps:

[0059] S1. After the epoxy resin and small molecule hydroxyl compound are mixed evenly, the additives and inorganic fillers are added in sequence and stirred on a high-speed disperser. After stirring, the mixture is allowed to stand to obtain component A material.

[0060] S2, when used, mix the A component material obtained from S1 with the curing agent to obtain a high-temperature resistant, room-temperature curing anti-corrosion coating.

[0061] Example 2

[0062] Example 2 provides a high-temperature resistant, room-temperature curing anti-corrosion coating. By weight, the coating comprises: Component A: 65 parts epoxy resin, 7 parts small-molecule hydroxyl compound, 3.5 parts additives, and 3.5 parts inorganic filler; Component B: 25 parts curing agent and 0.5 parts curing accelerator.

[0063] Epoxy resins include phenolic epoxy resins and silicone epoxy resins, with a weight ratio of phenolic epoxy resin to silicone epoxy resin of 1:0.35.

[0064] Phenolic epoxy resins include phenolic epoxy resins with a viscosity of 7000 to 2000 at 25°C;

[0065] The silicone epoxy resin includes RE-611 (purchased from Wuxi Xinuo New Materials, Ford cup 4, viscosity at 25℃ is 20-80s);

[0066] The small molecule polyhydroxy compound is trimethylolpropane triglycidyl ether;

[0067] Curing agents include polyetheramine and m-phenylenediamine;

[0068] The mass ratio of polyetheramine to m-phenylenediamine is 1:0.5;

[0069] Polyetheramines include the D2000 and T3000 of the Hongbaoli polyetheramine series, with a weight ratio of 1:0.7 between D2000 and T3000.

[0070] The curing accelerator is salicylic acid;

[0071] The inorganic filler is fumed silica, specifically Wacker fumed silica. H2O (BET is 170-230m) 2 / g, sample density is 40g / L);

[0072] The additive is an antifoaming agent, specifically VK.DF553;

[0073] The coating preparation method described in this embodiment includes the following steps:

[0074] S1. After the epoxy resin and small molecule hydroxyl compound are mixed evenly, the additives and inorganic fillers are added in sequence and stirred on a high-speed disperser. After stirring, the mixture is allowed to stand to obtain component A material.

[0075] S2, when used, mix the A component material obtained from S1 with the curing agent to obtain a high-temperature resistant, room-temperature curing anti-corrosion coating.

[0076] Example 3

[0077] Example 3 provides a high-temperature resistant, room-temperature curing anti-corrosion coating. By weight, the coating comprises: Component A: 65 parts epoxy resin, 7 parts small molecule hydroxyl compound, 3.5 parts additives, and 3.5 parts inorganic filler; Component B: 25 parts curing agent and 0.5 parts curing accelerator.

[0078] Epoxy resins include phenolic epoxy resins and silicone epoxy resins, with a weight ratio of phenolic epoxy resin to silicone epoxy resin of 1:0.35.

[0079] The phenolic epoxy resin includes phenolic epoxy resin with a viscosity of 1000-2000 at 25℃ and phenolic epoxy resin with a viscosity of 7000-2000 at 25℃; and the weight ratio of phenolic epoxy resin with a viscosity of 1000-2000 at 25℃ (Dow, DEN438-X8, 1000-2000 mPa.s at 25℃, epoxy equivalent of 176-181 g / eq) and phenolic epoxy resin with a viscosity of 7000-20000 at 25℃ (domestic linear phenolic epoxy resin EPN1183, 7000-11000 mPa.s at 25℃, epoxy value of 6.3-6.9 Eq / kg) is 1:3.2.

[0080] The silicone epoxy resins include RE-611 (purchased from Wuxi Xiano New Materials, Forecast cup 4, viscosity at 25℃ is 20-80s) and Dow Corning SF-8413 (viscosity at 25℃ is 15000-20000mPas), with a weight ratio of 1:2.2.

[0081] The small molecule polyhydroxy compound is trimethylolpropane triglycidyl ether;

[0082] Curing agents include polyetheramine and m-phenylenediamine;

[0083] The mass ratio of polyetheramine to m-phenylenediamine is 1:0.5;

[0084] Polyetheramines include D2000 from the Hongbaoli polyetheramine series;

[0085] The curing accelerator is salicylic acid;

[0086] The inorganic filler is fumed silica, specifically Wacker fumed silica. H2O (BET is 170-230m) 2 / g, sample density is 40g / L);

[0087] The additive is an antifoaming agent, specifically VK.DF553;

[0088] The coating preparation method described in this embodiment includes the following steps:

[0089] S1. After the epoxy resin and small molecule hydroxyl compound are mixed evenly, the additives and inorganic fillers are added in sequence and stirred on a high-speed disperser. After stirring, the mixture is allowed to stand to obtain component A material.

[0090] S2, when used, mix the A component material obtained from S1 with the curing agent to obtain a high-temperature resistant, room-temperature curing anti-corrosion coating.

[0091] Example 4

[0092] Unlike Example 1, the high-temperature resistant, room-temperature curing anti-corrosion coating of this embodiment comprises, by weight, component A: 50 parts epoxy resin, 5 parts small molecule hydroxyl compound, 2 parts additives, and 2 parts inorganic filler; and component B: 20 ​​parts curing agent and 0.5 parts curing accelerator.

[0093] Example 5

[0094] Unlike Example 1, the high-temperature resistant, room-temperature curing anti-corrosion coating of this embodiment comprises, by weight, component A: 70 parts epoxy resin, 10 parts small molecule hydroxyl compound, 5 parts additives, and 5 parts inorganic filler; and component B: 30 parts curing agent and 0.5 parts curing accelerator.

[0095] Example 6

[0096] Unlike Example 1, the silicone epoxy resin included only RE-611 (purchased from Wuxi Xiano New Materials, Forte 4 cup, viscosity of 20-80s at 25°C).

[0097] Example 7

[0098] Unlike Example 1, the silicone epoxy resin included only Dow Corning SF-8413 (viscosity of 15000-20000 mPa·s at 25°C).

[0099] Example 8

[0100] Unlike Example 1, the phenolic epoxy resin includes only phenolic epoxy resin with a viscosity of 1000-2000 at 25°C.

[0101] Example 9

[0102] Unlike Example 1, the phenolic epoxy resin includes only phenolic epoxy resin with a viscosity of 7000 to 2000 at 25°C.

[0103] Example 10

[0104] Unlike Example 1, the polyetheramine used is T3000 from the Red Poly etheramine series.

[0105] Example 11

[0106] Unlike Example 1, the curing agent is m-phenylenediamine.

[0107] Example 12

[0108] Unlike Example 1, the curing accelerator content is 0.

[0109] Performance testing:

[0110] The coatings in Examples 1-12 were subjected to performance tests. Before coating, the surface of the N80 steel plate sample was sandblasted to achieve a surface roughness grade of Sa 2.5. Then, the coating was brushed onto the N80 steel plate of the same specification. After brushing, the sample was left to stand at 25°C for 21 days to ensure that the dry film thickness was 250±15 micrometers.

[0111] 1. Adhesion test:

[0112] (1) The adhesion was tested after being placed in a humid high temperature (3.5% NaCl aqueous solution, 150℃) for 168 hours;

[0113] (2) The adhesion was tested after 16 hours in System 1: liquid phase: NaOH solution, pH value: 12.5, temperature: 148℃, pressure: 70MPa; System 2: liquid phase: water, toluene and kerosene three phases, temperature: 107℃, pressure: 35MPa, gas phase: 100% CO2.

[0114] The method for testing adhesion is as follows:

[0115] Referring to SY / T 6717-2016, 5A indicates no peeling or flaking; 4A indicates peeling or flaking along the knife mark; 3A indicates flaking up to 1.6mm with notches on both sides of the knife mark; 2A indicates flaking up to 3.2mm with notches on both sides of the knife mark; and 1A indicates significant flaking.

[0116] Table 1. Results of Coating Adhesion Test

[0117]

[0118] As shown in Table 1, the high-temperature resistant room-temperature curing anti-corrosion coatings of Examples 1 to 5, compared with other examples, showed no bubbles in the coatings under humid high temperature, high temperature and high pressure NaOH and high temperature and high pressure CO2 environments, and most of them did not peel off significantly along the knife marks.

[0119] 2. Bending toughness test:

[0120] The coated sample was placed in a -20°C environmental chamber for 8 hours, and then quickly removed and subjected to a 2.5° bending test on a bending tester to evaluate whether the coated sample cracked.

[0121] Table 2 Results of Bending Toughness Test

[0122]

[0123] As shown in Tables 1 and 2, the high-temperature resistant, room-temperature curing anti-corrosion coating of this embodiment performed well in both adhesion and bending tests, demonstrating excellent adhesion and bending properties.

[0124] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

[0125] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0126] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A high-temperature resistant, room-temperature curing anti-corrosion coating, characterized in that, It includes component A and component B. Component A includes epoxy resin, small molecule hydroxyl compound, additives and inorganic filler, and component B includes curing agent. The epoxy resin includes phenolic epoxy resin, which includes a variety of phenolic epoxy resins with different viscosity gradients.

2. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, The phenolic epoxy resin includes phenolic epoxy resin with a viscosity of 1000-2000 mPa·s at 25°C and phenolic epoxy resin with a viscosity of 7000-20000 mPa·s at 25°C. The epoxy equivalent of phenolic epoxy resin with a viscosity of 1000-2000 mPa·s at 25℃ is 176-181 g / eq. The epoxy equivalent of phenolic epoxy resin with a viscosity of 7000–20000 mPa·s at 25℃ is 14–16 kg / eq.

3. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, The epoxy resin further includes organosilicon epoxy resin, and the weight ratio of phenolic epoxy resin to organosilicon epoxy resin is 1:(0.25~0.45). The silicone epoxy resin includes a variety of silicone epoxy resins with different viscosity gradients.

4. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 3, characterized in that, The organosilicon epoxy resin includes a Forte 4 cup with a viscosity of 20-80 s at 25°C and an organosilicon modified epoxy resin with a viscosity of 15000-20000 mPa·s. The weight ratio of organosilicon epoxy resin with a viscosity of 20-80 s at 25°C (using a Forte 4 cup) to organosilicon modified epoxy resin with a viscosity of 15000-20000 mPa·s is 1:(1.6-2.7).

5. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, The small molecule hydroxy compound is trimethylolpropane triglycidyl ether.

6. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, The curing agent is a polyetheramine with a total amine value of 0.5–1.1 Meq / g; The primary amine content of the polyetheramine is not less than 95%, and the viscosity at 25°C is 200–700 mPa·s.

7. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 6, characterized in that, The polyetheramines include D2000 and T3000 from the Red Power polyetheramine series, with a weight ratio of 1:(0.5 to 0.7).

8. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, The inorganic filler has a BET specific surface area of ​​150–300 m². 2 / g of fumed silica, wherein the sample density of the inorganic filler is 30-50g / L.

9. The high-temperature resistant, room-temperature curing anti-corrosion coating according to claim 1, characterized in that, By weight, component A includes 50-70 parts epoxy resin, 5-10 parts small molecule hydroxyl compound, 2-5 parts additives and 2-5 parts inorganic filler, and component B includes 20-30 parts curing agent. The epoxy resin includes phenolic epoxy resin, which comprises two phenolic epoxy resins with different viscosity gradients. The weight ratio of the phenolic epoxy resin with a smaller viscosity gradient to the phenolic epoxy resin with a larger viscosity gradient is 1:(2.5-3.8).

10. A method for preparing a high-temperature resistant, room-temperature curing anti-corrosion coating according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1, after the epoxy resin and small molecule hydroxy compound are mixed evenly, the additives and inorganic fillers are added in sequence and stirred on a high-speed dispersant. After stirring, the mixture is allowed to stand to obtain component A material. S2, when used, mix the A component material obtained from S1 with the curing agent to obtain a high-temperature resistant, room-temperature curing anti-corrosion coating.

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